It is similar to the SCAN disk scheduling algorithm except for the difference that the disk arm in spite of going to the end of the disk goes only to the last request to be serviced in front of the head and then reverses its direction from there only. Thus it prevents the extra delay which occurred due to unnecessary traversal to the end of the disk.

1. In Look disk scheduling, there is no starvation.


2. Look disk scheduling offers low variance in waiting time and response time.


3. Look disk scheduling offers better performance as compared to the SCAN disk scheduling.


4. In look disk scheduling, there is no requirement of disk head to move till the end to the disk.

1. In look disk scheduling, there is more overhead to find the end request.


2. Look disk scheduling is not used in case of more load.

1. Let Request array represents an array storing indexes of tracks that have been requested in ascending order of their time of arrival. ‘head’ is the position of disk head.


2. The initial direction in which head is moving is given and it services in the same direction.


3. The head services all the requests one by one in the direction head is moving.


4. While moving in this direction calculate the absolute distance of the track from the head.


5. Increment the total seek count with this distance.


6. Currently serviced track position now becomes the new head position.


7. Go to step 5 until we reach at last request in this direction.


8. The head continues to move in the same direction until all the request in this direction are not finished.


9. If we reach where no requests are needed to be serviced in this direction reverse the direction and go to step 3 until all tracks in request array have not been serviced.